function UrlUtil() { };  
 /// <summary>  
 /// Url帮助函数库  
 /// </summary>  
   
 UrlUtil.getURLParameters = function() {  
 /// <summary>  
 /// alert显示参数  
 /// </summary>  
     var sURL = window.document.URL.toString();  
   
     if (sURL.indexOf("?") > 0) {  
         var arrParams = sURL.split("?");  
   
         var arrURLParams = arrParams[1].split("&");  
   
         var arrParamNames = new Array(arrURLParams.length);  
         var arrParamValues = new Array(arrURLParams.length);  
   
         var i = 0;  
         for (i = 0; i < arrURLParams.length; i++) {  
             var sParam = arrURLParams[i].split("=");  
             arrParamNames[i] = sParam[0];  
             if (sParam[1] != "")  
                 arrParamValues[i] = unescape(sParam[1]);  
             else  
                 arrParamValues[i] = "No Value";  
         }  
   
         for (i = 0; i < arrURLParams.length; i++) {  
             alert(arrParamNames[i] + " = " + arrParamValues[i]);  
         }  
     }  
     else {  
         alert("No parameters.");  
     }  
 };  
   
 /** 
  * Add a parameter to the url 
  */  
 UrlUtil.addParameter = function(href, name, value) {  
 ///<summary>  
 ///添加参数,若是更改,请先移除再添加之  
 ///</summary>  
       
     var delimiter;  
     if (href.indexOf("?") == -1)  
         delimiter = "?";  
     else  
         delimiter = "&";  
     return href + delimiter + name + "=" + value;  
 };  
 
   
   
 /**  
  * remove the parameter from an url 
  */  
 UrlUtil.removeParameter = function(href, name) {  
 ///<summary>  
 ///移除参数,works only for a single paramter  
 ///</summary>  
   
     var tmp = href.split("?");  
   
     var newHref = tmp[0];  
     var query = new Array();  
     if (tmp[1]) {  
         var paramObj = tmp[1].split("&");  
   
         for (var i = 0; i < paramObj.length; i++) {  
             if (paramObj[i].indexOf(name + "=") != 0) {  
                 query.push(paramObj[i]);  
             }  
         }  
     }  
   
     if (query.length > 0) {  
         newHref += "?";  
   
         for (var i = 0; i < query.length; i++) {  
             newHref += query[i];  
   
             if (i + 1 < query.length) {  
                 newHref += "&";  
             }  
         }  
     }  
   
     return newHref;  
 };  
   
 /** 
  * Is this an external URL containing :// 
  */  
 UrlUtil.isExternal = function(url) {  
 ///<summary>  
 ///Url是否包含"://"符号串  
 ///</summary>  
     return url.indexOf("://") != -1;  
 };  
 
 function req_link(name,value){
	var url = window.location.href;
	url = UrlUtil.removeParameter(url,name);
	var new_url = UrlUtil.addParameter(url,name,value);
	location.href = new_url;
};